By School Mathematics Project
By Lister, Raymond.
By Barber, James
By Manning
By Fabian, Johannes
By Gifford, Paul
By Williams, R. R.
By Leaney, A.R. Leaney
By Cook, Helen, Styles, Morag
By Hicks, Diana, Pote, Michael, Esnol, Armel, Wright, Derek
By McRae, John, Boardman, Roy
By WHITBY, Norman
By Boesch, Christophe
By Forey, P. L., Greenwood, P. H.
By Moore, N
By O'Dell, Felicity
By Jones, Leo
By Fage, J. D.
By Cambridge ESOL
By Jakeman, Vanessa, McDowell, Clare
By Schraeder, Peter J.
By Wyse, Akintola
By O'Brien, Donal Cruise, Dunn, John, Rathbone, Richard